/* -----------------------------------------------------------------------------
 * Programmer(s): Daniel R. Reynolds @ SMU
 * -----------------------------------------------------------------------------
 * SUNDIALS Copyright Start
 * Copyright (c) 2002-2025, Lawrence Livermore National Security
 * and Southern Methodist University.
 * All rights reserved.
 *
 * See the top-level LICENSE and NOTICE files for details.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 * SUNDIALS Copyright End
 * -----------------------------------------------------------------------------
 * Routine to test the accuracy of the ARKodeInterp modules, using
 * the problem
 *   [y'] = [ lambda*(y - sin(2*t)) + z - cos(3*t) + 2*cos(2*t) ]
 *   [z']   [     y - z - sin(2*t) + cos(3*t) - 3*sin(3*t)      ]
 *   [y(0); z(0)] = [0; 1]
 * for various values of lambda<0.  This has analytical solution
 *   [y(t); z(t)] = [sin(2*t); cos(3*t)]
 * ---------------------------------------------------------------------------*/

/* Header files */
#include <arkode/arkode_arkstep.h>
#include <math.h>
#include <nvector/nvector_serial.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sundials/sundials_math.h>
#include <sunlinsol/sunlinsol_dense.h>
#include <sunnonlinsol/sunnonlinsol_newton.h>

#define NHVALS 9

/* Precision specific math function macros */
#if defined(SUNDIALS_DOUBLE_PRECISION)
#define SIN(x)  (sin((x)))
#define COS(x)  (cos((x)))
#define SQRT(x) (sqrt((x)))
#elif defined(SUNDIALS_SINGLE_PRECISION)
#define SIN(x)  (sinf((x)))
#define COS(x)  (cosf((x)))
#define SQRT(x) (sqrtf((x)))
#elif defined(SUNDIALS_EXTENDED_PRECISION)
#define SIN(x)  (sinl((x)))
#define COS(x)  (cosl((x)))
#define SQRT(x) (sqrtl((x)))
#endif

/* User-supplied Functions Called by the Solver */
static int f(sunrealtype t, N_Vector y, N_Vector ydot, void* user_data);

/* Private function to check function return values */
static int check_flag(void* flagvalue, const char* funcname, int opt);

/* Private function to verify test results */
static int verify_results(sunrealtype lambda, int rtype, sunrealtype* yrate,
                          sunrealtype* dyrate, sunrealtype* d2yrate,
                          sunrealtype* yrate2, sunrealtype* dyrate2,
                          sunrealtype* d2yrate2);

/* Main Program */
int main(int argc, char* argv[])
{
  /* initial declaration of all variables */
  sunrealtype T0, Tf, lambda, t, t_test, hbase, rtol, atol;
  sunindextype NEQ;
  int flag, nttest, ideg, ih, itest, rtype;
  N_Vector y, ytest, dytest, d2ytest, d3ytest, d4ytest, d5ytest;
  N_Vector yerr, dyerr, d2yerr, d3yerr, d4yerr, d5yerr;
  SUNMatrix A;
  SUNLinearSolver LS;
  void* arkode_mem;
  sunrealtype hvals[NHVALS], yerrs[NHVALS], dyerrs[NHVALS], d2yerrs[NHVALS];
  sunrealtype d3yerrs[NHVALS], d4yerrs[NHVALS], d5yerrs[NHVALS];
  sunrealtype yrate[ARK_INTERP_MAX_DEGREE + 1], dyrate[ARK_INTERP_MAX_DEGREE + 1];
  sunrealtype d2yrate[ARK_INTERP_MAX_DEGREE + 1],
    d3yrate[ARK_INTERP_MAX_DEGREE + 1];
  sunrealtype d4yrate[ARK_INTERP_MAX_DEGREE + 1],
    d5yrate[ARK_INTERP_MAX_DEGREE + 1];
  sunrealtype yferr[ARK_INTERP_MAX_DEGREE + 1], dyferr[ARK_INTERP_MAX_DEGREE + 1];
  sunrealtype d2yferr[ARK_INTERP_MAX_DEGREE + 1],
    d3yferr[ARK_INTERP_MAX_DEGREE + 1];
  sunrealtype d4yferr[ARK_INTERP_MAX_DEGREE + 1],
    d5yferr[ARK_INTERP_MAX_DEGREE + 1];
  sunrealtype yrate2[ARK_INTERP_MAX_DEGREE + 1],
    dyrate2[ARK_INTERP_MAX_DEGREE + 1];
  sunrealtype d2yrate2[ARK_INTERP_MAX_DEGREE + 1],
    yferr2[ARK_INTERP_MAX_DEGREE + 1];
  sunrealtype dyferr2[ARK_INTERP_MAX_DEGREE + 1],
    d2yferr2[ARK_INTERP_MAX_DEGREE + 1];

  /* Create the SUNDIALS context object for this simulation. */
  SUNContext sunctx = NULL;
  SUNContext_Create(SUN_COMM_NULL, &sunctx);

  /* general problem parameters */
  T0  = SUN_RCONST(0.0);  /* initial time */
  Tf  = SUN_RCONST(10.0); /* final time */
  NEQ = 2;                /* number of dependent vars. */

  /* if an argument supplied, set lambda (otherwise use -100) */
  lambda = -SUN_RCONST(100.0);
  if (argc > 1) { lambda = strtod(argv[1], NULL); }

  /* determine test configuration */
  if (sizeof(sunrealtype) == 4) { rtype = 32; }
  else if (sizeof(sunrealtype) == 8) { rtype = 64; }
  else { rtype = 128; }

  /* set IVP solver tolerances based on rtype */
  if (rtype == 32)
  {
    rtol = 1e-7;
    atol = 1e-7;
  }
  else if (rtype == 64)
  {
    rtol = 1e-14;
    atol = 1e-14;
  }
  else
  {
    rtol = 1e-19;
    atol = 1e-20;
  }

  /* initialize vector/solver objects to NULL */
  y = ytest = dytest = d2ytest = d3ytest = d4ytest = d5ytest = NULL;
  yerr = dyerr = d2yerr = d3yerr = d4yerr = d5yerr = NULL;
  A                                                = NULL;
  LS                                               = NULL;
  arkode_mem                                       = NULL;

  /* Initial problem output */
  printf("\nARKode Interpolation module tester (rtype = %i):\n", rtype);

  /* Initialize vectors */
  y = N_VNew_Serial(NEQ, sunctx);
  if (check_flag((void*)y, "N_VNew_Serial", 0)) { return 1; }
  ytest = N_VClone(y);
  if (check_flag((void*)ytest, "N_VNew_Serial", 0)) { return 1; }
  dytest = N_VClone(y);
  if (check_flag((void*)dytest, "N_VNew_Serial", 0)) { return 1; }
  d2ytest = N_VClone(y);
  if (check_flag((void*)d2ytest, "N_VNew_Serial", 0)) { return 1; }
  d3ytest = N_VClone(y);
  if (check_flag((void*)d3ytest, "N_VNew_Serial", 0)) { return 1; }
  d4ytest = N_VClone(y);
  if (check_flag((void*)d4ytest, "N_VNew_Serial", 0)) { return 1; }
  d5ytest = N_VClone(y);
  if (check_flag((void*)d5ytest, "N_VNew_Serial", 0)) { return 1; }
  yerr = N_VClone(y);
  if (check_flag((void*)yerr, "N_VNew_Serial", 0)) { return 1; }
  dyerr = N_VClone(y);
  if (check_flag((void*)dyerr, "N_VNew_Serial", 0)) { return 1; }
  d2yerr = N_VClone(y);
  if (check_flag((void*)d2yerr, "N_VNew_Serial", 0)) { return 1; }
  d3yerr = N_VClone(y);
  if (check_flag((void*)d3yerr, "N_VNew_Serial", 0)) { return 1; }
  d4yerr = N_VClone(y);
  if (check_flag((void*)d4yerr, "N_VNew_Serial", 0)) { return 1; }
  d5yerr = N_VClone(y);
  if (check_flag((void*)d5yerr, "N_VNew_Serial", 0)) { return 1; }

  /* initialize algebraic solver structures */
  A = SUNDenseMatrix(NEQ, NEQ, sunctx);
  if (check_flag((void*)A, "SUNDenseMatrix", 0)) { return 1; }
  LS = SUNLinSol_Dense(y, A, sunctx);
  if (check_flag((void*)LS, "SUNLinSol_Dense", 0)) { return 1; }

  /* test parameters */
  nttest = 500;
  hbase  = SUN_RCONST(2.0);

  /*---- Part I: Hermite interpolation module ----*/
  printf("\nHermite interpolation module tests:\n");

  /* loop over dense output polynomial degrees */
  for (ideg = 0; ideg <= ARK_INTERP_MAX_DEGREE; ideg++)
  {
    /* reset error/convergence arrays */
    for (ih = 0; ih < NHVALS; ih++)
    {
      yerrs[ih]   = SUN_RCONST(0.0);
      dyerrs[ih]  = SUN_RCONST(0.0);
      d2yerrs[ih] = SUN_RCONST(0.0);
      d3yerrs[ih] = SUN_RCONST(0.0);
      d4yerrs[ih] = SUN_RCONST(0.0);
      d5yerrs[ih] = SUN_RCONST(0.0);
    }

    /* run tests for this dense output polynomial degree */
    for (ih = 0; ih < NHVALS; ih++)
    {
      /* set test stepsize */
      hvals[ih] = SUN_RCONST(2.0) / pow(hbase, ih);

      /* Initialize y values */
      NV_Ith_S(y, 0) = SUN_RCONST(0.0);
      NV_Ith_S(y, 1) = SUN_RCONST(1.0);

      /* Create/initialize ARKStep module */
      arkode_mem = ARKStepCreate(NULL, f, T0, y, sunctx);
      if (check_flag(arkode_mem, "ARKStepCreate", 0)) { return 1; }

      /* pass lambda to RHS routine */
      flag = ARKodeSetUserData(arkode_mem, &lambda);
      if (check_flag(&flag, "ARKodeSetUserData", 1)) { return 1; }

      /* select Hermite interpolation module */
      flag = ARKodeSetInterpolantType(arkode_mem, ARK_INTERP_HERMITE);
      if (check_flag(&flag, "ARKodeSetInterpolantType", 1)) { return 1; }

      /* set dense output polynomial degree */
      flag = ARKodeSetInterpolantDegree(arkode_mem, ideg);
      if (check_flag(&flag, "ARKodeSetInterpolantDegree", 1)) { return 1; }

      /* set fixed time-stepping with desired time step size */
      flag = ARKodeSetFixedStep(arkode_mem, hvals[ih]);
      if (check_flag(&flag, "ARKodeSetFixedStep", 1)) { return 1; }

      /* set solver tolerances */
      flag = ARKodeSStolerances(arkode_mem, rtol, atol);
      if (check_flag(&flag, "ARKodeSStolerances", 1)) { return 1; }

      /* indicate linearity of problem */
      flag = ARKodeSetLinear(arkode_mem, 0);
      if (check_flag(&flag, "ARKodeSetLinear", 1)) { return 1; }

      /* attach linear solver */
      flag = ARKodeSetLinearSolver(arkode_mem, LS, A);
      if (check_flag(&flag, "ARKodeSetLinearSolver", 1)) { return 1; }

      /* increase maximum number of time steps */
      flag = ARKodeSetMaxNumSteps(arkode_mem, 100000);
      if (check_flag(&flag, "ARKodeSetMaxNumSteps", 1)) { return 1; }

      /* set RK order to highest available value */
      flag = ARKodeSetOrder(arkode_mem, 5);
      if (check_flag(&flag, "ARKodeSetOrder", 1)) { return 1; }

      /* evolve to Tf to prepare interpolation structure */
      flag = ARKodeSetStopTime(arkode_mem, Tf);
      if (check_flag(&flag, "ARKodeSetStopTime", 1)) { return 1; }
      flag = ARKodeEvolve(arkode_mem, Tf, y, &t, ARK_NORMAL);
      if (check_flag(&flag, "ARKodeEvolve", 1)) { return 1; }

      /* loop over 100 evenly-spaced values within interior of preceding
         step to accumulate errors */
      for (itest = 0; itest < nttest; itest++)
      {
        /* set test time */
        t_test = t - hvals[ih] + (itest + 1) * hvals[ih] / (nttest + 2);

        /* call ARKodeGetDky to evaluate solution and derivatives at t_test */
        flag = ARKodeGetDky(arkode_mem, t_test, 0, ytest);
        if (check_flag(&flag, "ARKodeGetDky", 1)) { return 1; }
        flag = ARKodeGetDky(arkode_mem, t_test, 1, dytest);
        if (check_flag(&flag, "ARKodeGetDky", 1)) { return 1; }
        flag = ARKodeGetDky(arkode_mem, t_test, 2, d2ytest);
        if (check_flag(&flag, "ARKodeGetDky", 1)) { return 1; }
        flag = ARKodeGetDky(arkode_mem, t_test, 3, d3ytest);
        if (check_flag(&flag, "ARKodeGetDky", 1)) { return 1; }
        flag = ARKodeGetDky(arkode_mem, t_test, 4, d4ytest);
        if (check_flag(&flag, "ARKodeGetDky", 1)) { return 1; }
        flag = ARKodeGetDky(arkode_mem, t_test, 5, d5ytest);
        if (check_flag(&flag, "ARKodeGetDky", 1)) { return 1; }

        /* set error values */
        /*   y */
        NV_Ith_S(yerr, 0) =
          SUNRabs(SIN(SUN_RCONST(2.0) * t_test) - NV_Ith_S(ytest, 0));
        NV_Ith_S(yerr, 1) =
          SUNRabs(COS(SUN_RCONST(3.0) * t_test) - NV_Ith_S(ytest, 1));
        /*   dy */
        NV_Ith_S(dyerr, 0) = SUNRabs(
          SUN_RCONST(2.0) * COS(SUN_RCONST(2.0) * t_test) - NV_Ith_S(dytest, 0));
        NV_Ith_S(dyerr, 1) = SUNRabs(
          -SUN_RCONST(3.0) * SIN(SUN_RCONST(3.0) * t_test) - NV_Ith_S(dytest, 1));
        /*   d2y */
        NV_Ith_S(d2yerr,
                 0) = SUNRabs(-SUN_RCONST(4.0) * SIN(SUN_RCONST(2.0) * t_test) -
                              NV_Ith_S(d2ytest, 0));
        NV_Ith_S(d2yerr,
                 1) = SUNRabs(-SUN_RCONST(9.0) * COS(SUN_RCONST(3.0) * t_test) -
                              NV_Ith_S(d2ytest, 1));
        /*   d3y */
        NV_Ith_S(d3yerr,
                 0) = SUNRabs(-SUN_RCONST(8.0) * COS(SUN_RCONST(2.0) * t_test) -
                              NV_Ith_S(d3ytest, 0));
        NV_Ith_S(d3yerr,
                 1) = SUNRabs(SUN_RCONST(27.0) * SIN(SUN_RCONST(3.0) * t_test) -
                              NV_Ith_S(d3ytest, 1));
        /*   d4y */
        NV_Ith_S(d4yerr,
                 0) = SUNRabs(SUN_RCONST(16.0) * SIN(SUN_RCONST(2.0) * t_test) -
                              NV_Ith_S(d4ytest, 0));
        NV_Ith_S(d4yerr,
                 1) = SUNRabs(SUN_RCONST(81.0) * COS(SUN_RCONST(3.0) * t_test) -
                              NV_Ith_S(d4ytest, 1));
        /*   d5y */
        NV_Ith_S(d5yerr,
                 0) = SUNRabs(SUN_RCONST(32.0) * COS(SUN_RCONST(2.0) * t_test) -
                              NV_Ith_S(d5ytest, 0));
        NV_Ith_S(d5yerr, 1) =
          SUNRabs(-SUN_RCONST(243.0) * SIN(SUN_RCONST(3.0) * t_test) -
                  NV_Ith_S(d5ytest, 1));

        /* compute error norms (2-norm per test, max-norm over interval) */
        yerrs[ih]   = SUNMAX(yerrs[ih], SQRT(N_VDotProd(yerr, yerr)));
        dyerrs[ih]  = SUNMAX(dyerrs[ih], SQRT(N_VDotProd(dyerr, dyerr)));
        d2yerrs[ih] = SUNMAX(d2yerrs[ih], SQRT(N_VDotProd(d2yerr, d2yerr)));
        d3yerrs[ih] = SUNMAX(d3yerrs[ih], SQRT(N_VDotProd(d3yerr, d3yerr)));
        d4yerrs[ih] = SUNMAX(d4yerrs[ih], SQRT(N_VDotProd(d4yerr, d4yerr)));
        d5yerrs[ih] = SUNMAX(d5yerrs[ih], SQRT(N_VDotProd(d5yerr, d5yerr)));

      } /* end itest loop */

      /* free ARKode memory (to prepare for next call) */
      ARKodeFree(&arkode_mem);
      arkode_mem = NULL;

    } /* end ih loop */

    printf("\nConvergence Test Results, dense output polynomial degree = %i:\n",
           ideg);
    printf("\n  Raw errors per h value:\n");
    printf("  "
           "-------------------------------------------------------------------"
           "-----------\n");
    printf("    h         yerr       dyerr      d2yerr     d3yerr    d4yerr   "
           "d5yerr\n");
    printf("  "
           "-------------------------------------------------------------------"
           "-----------\n");
    for (ih = 0; ih < NHVALS; ih++)
    {
      printf("    %.1e   %.2e   %.2e   %.2e   %.2e   %.2e   %.2e\n",
             (double)hvals[ih], (double)yerrs[ih], (double)dyerrs[ih],
             (double)d2yerrs[ih], (double)d3yerrs[ih], (double)d4yerrs[ih],
             (double)d5yerrs[ih]);
    }
    printf("  "
           "-------------------------------------------------------------------"
           "-----------\n");

    printf("  Estimated y convergence factors:\n  ");
    for (ih = 1; ih < NHVALS; ih++)
    {
      printf("  %.3f",
             log(yerrs[ih] / yerrs[ih - 1]) / log(hvals[ih] / hvals[ih - 1]));
    }
    yrate[ideg] = log(yerrs[NHVALS - 1] / yerrs[0]) /
                  log(hvals[NHVALS - 1] / hvals[0]);
    yferr[ideg] = yerrs[NHVALS - 1];
    printf("  (%.3f, %.0e)\n\n", (double)yrate[ideg], (double)yferr[ideg]);

    printf("  Estimated dy convergence factors:\n  ");
    for (ih = 1; ih < NHVALS; ih++)
    {
      printf("  %.3f",
             log(dyerrs[ih] / dyerrs[ih - 1]) / log(hvals[ih] / hvals[ih - 1]));
    }
    dyrate[ideg] = log(dyerrs[NHVALS - 1] / dyerrs[0]) /
                   log(hvals[NHVALS - 1] / hvals[0]);
    dyferr[ideg] = dyerrs[NHVALS - 1];
    printf("  (%.3f, %.0e)\n\n", (double)dyrate[ideg], (double)dyferr[ideg]);

    printf("  Estimated d2y convergence factors:\n  ");
    for (ih = 1; ih < NHVALS; ih++)
    {
      printf("  %.3f", log(d2yerrs[ih] / d2yerrs[ih - 1]) /
                         log(hvals[ih] / hvals[ih - 1]));
    }
    d2yrate[ideg] = log(d2yerrs[NHVALS - 1] / d2yerrs[0]) /
                    log(hvals[NHVALS - 1] / hvals[0]);
    d2yferr[ideg] = d2yerrs[NHVALS - 1];
    printf("  (%.3f, %.0e)\n\n", (double)d2yrate[ideg], (double)d2yferr[ideg]);

    printf("  Estimated d3y convergence factors:\n  ");
    for (ih = 1; ih < NHVALS; ih++)
    {
      printf("  %.3f", log(d3yerrs[ih] / d3yerrs[ih - 1]) /
                         log(hvals[ih] / hvals[ih - 1]));
    }
    d3yrate[ideg] = log(d3yerrs[NHVALS - 1] / d3yerrs[0]) /
                    log(hvals[NHVALS - 1] / hvals[0]);
    d3yferr[ideg] = d3yerrs[NHVALS - 1];
    printf("  (%.3f, %.0e)\n\n", (double)d3yrate[ideg], (double)d3yferr[ideg]);

    printf("  Estimated d4y convergence factors:\n  ");
    for (ih = 1; ih < NHVALS; ih++)
    {
      printf("  %.3f", log(d4yerrs[ih] / d4yerrs[ih - 1]) /
                         log(hvals[ih] / hvals[ih - 1]));
    }
    d4yrate[ideg] = log(d4yerrs[NHVALS - 1] / d4yerrs[0]) /
                    log(hvals[NHVALS - 1] / hvals[0]);
    d4yferr[ideg] = d4yerrs[NHVALS - 1];
    printf("  (%.3f, %.0e)\n\n", (double)d4yrate[ideg], (double)d4yferr[ideg]);

    printf("  Estimated d5y convergence factors:\n  ");
    for (ih = 1; ih < NHVALS; ih++)
    {
      printf("  %.3f", log(d5yerrs[ih] / d5yerrs[ih - 1]) /
                         log(hvals[ih] / hvals[ih - 1]));
    }
    d5yrate[ideg] = log(d5yerrs[NHVALS - 1] / d5yerrs[0]) /
                    log(hvals[NHVALS - 1] / hvals[0]);
    d5yferr[ideg] = d5yerrs[NHVALS - 1];
    printf("  (%.3f, %.0e)\n\n", (double)d5yrate[ideg], (double)d5yferr[ideg]);

  } /* end ideg loop */

  /*---- Part II: Lagrange interpolation module ----*/

  printf("\nLagrange interpolation module tests:\n");

  /* loop over dense output polynomial degrees */
  for (ideg = 0; ideg <= ARK_INTERP_MAX_DEGREE; ideg++)
  {
    /* reset error/convergence arrays */
    for (ih = 0; ih < NHVALS; ih++)
    {
      yerrs[ih]   = SUN_RCONST(0.0);
      dyerrs[ih]  = SUN_RCONST(0.0);
      d2yerrs[ih] = SUN_RCONST(0.0);
    }

    /* run tests for this dense output polynomial degree */
    for (ih = 0; ih < NHVALS; ih++)
    {
      /* set test stepsize */
      hvals[ih] = SUN_RCONST(2.0) / pow(hbase, ih);

      /* Initialize y values */
      NV_Ith_S(y, 0) = SUN_RCONST(0.0);
      NV_Ith_S(y, 1) = SUN_RCONST(1.0);

      /* Create/initialize ARKStep module */
      arkode_mem = ARKStepCreate(NULL, f, T0, y, sunctx);
      if (check_flag(arkode_mem, "ARKStepCreate", 0)) { return 1; }

      /* pass lambda to RHS routine */
      flag = ARKodeSetUserData(arkode_mem, &lambda);
      if (check_flag(&flag, "ARKodeSetUserData", 1)) { return 1; }

      /* select Lagrange interpolation module */
      flag = ARKodeSetInterpolantType(arkode_mem, ARK_INTERP_LAGRANGE);
      if (check_flag(&flag, "ARKodeSetInterpolantType", 1)) { return 1; }

      /* set dense output polynomial degree */
      flag = ARKodeSetInterpolantDegree(arkode_mem, ideg);
      if (check_flag(&flag, "ARKodeSetInterpolantDegree", 1)) { return 1; }

      /* set fixed time-stepping with desired time step size */
      flag = ARKodeSetFixedStep(arkode_mem, hvals[ih]);
      if (check_flag(&flag, "ARKodeSetFixedStep", 1)) { return 1; }

      /* set solver tolerances */
      flag = ARKodeSStolerances(arkode_mem, rtol, atol);
      if (check_flag(&flag, "ARKodeSStolerances", 1)) { return 1; }

      /* indicate linearity of problem */
      flag = ARKodeSetLinear(arkode_mem, 0);
      if (check_flag(&flag, "ARKodeSetLinear", 1)) { return 1; }

      /* attach linear solver */
      flag = ARKodeSetLinearSolver(arkode_mem, LS, A);
      if (check_flag(&flag, "ARKodeSetLinearSolver", 1)) { return 1; }

      /* increase maximum number of time steps */
      flag = ARKodeSetMaxNumSteps(arkode_mem, 100000);
      if (check_flag(&flag, "ARKodeSetMaxNumSteps", 1)) { return 1; }

      /* set RK order to highest available value */
      flag = ARKodeSetOrder(arkode_mem, 5);
      if (check_flag(&flag, "ARKodeSetOrder", 1)) { return 1; }

      /* evolve to Tf to prepare interpolation structure */
      flag = ARKodeSetStopTime(arkode_mem, Tf);
      if (check_flag(&flag, "ARKodeSetStopTime", 1)) { return 1; }
      flag = ARKodeEvolve(arkode_mem, Tf, y, &t, ARK_NORMAL);
      if (check_flag(&flag, "ARKodeEvolve", 1)) { return 1; }

      /* loop over 100 evenly-spaced values within interior of this step to accumulate errors */
      for (itest = 0; itest < nttest; itest++)
      {
        /* set test time */
        t_test = t - hvals[ih] + (itest + 1) * hvals[ih] / (nttest + 2);

        /* call ARKodeGetDky to evaluate solution and derivatives at t_test */
        flag = ARKodeGetDky(arkode_mem, t_test, 0, ytest);
        if (check_flag(&flag, "ARKodeGetDky", 1)) { return 1; }
        flag = ARKodeGetDky(arkode_mem, t_test, 1, dytest);
        if (check_flag(&flag, "ARKodeGetDky", 1)) { return 1; }
        flag = ARKodeGetDky(arkode_mem, t_test, 2, d2ytest);
        if (check_flag(&flag, "ARKodeGetDky", 1)) { return 1; }

        /* set error values */
        /*   y */
        NV_Ith_S(yerr, 0) =
          SUNRabs(SIN(SUN_RCONST(2.0) * t_test) - NV_Ith_S(ytest, 0));
        NV_Ith_S(yerr, 1) =
          SUNRabs(COS(SUN_RCONST(3.0) * t_test) - NV_Ith_S(ytest, 1));
        /*   dy */
        NV_Ith_S(dyerr, 0) = SUNRabs(
          SUN_RCONST(2.0) * COS(SUN_RCONST(2.0) * t_test) - NV_Ith_S(dytest, 0));
        NV_Ith_S(dyerr, 1) = SUNRabs(
          -SUN_RCONST(3.0) * SIN(SUN_RCONST(3.0) * t_test) - NV_Ith_S(dytest, 1));
        /*   d2y */
        NV_Ith_S(d2yerr,
                 0) = SUNRabs(-SUN_RCONST(4.0) * SIN(SUN_RCONST(2.0) * t_test) -
                              NV_Ith_S(d2ytest, 0));
        NV_Ith_S(d2yerr,
                 1) = SUNRabs(-SUN_RCONST(9.0) * COS(SUN_RCONST(3.0) * t_test) -
                              NV_Ith_S(d2ytest, 1));

        /* compute error norms (2-norm per test, max-norm over interval) */
        yerrs[ih]   = SUNMAX(yerrs[ih], SQRT(N_VDotProd(yerr, yerr)));
        dyerrs[ih]  = SUNMAX(dyerrs[ih], SQRT(N_VDotProd(dyerr, dyerr)));
        d2yerrs[ih] = SUNMAX(d2yerrs[ih], SQRT(N_VDotProd(d2yerr, d2yerr)));

      } /* end itest loop */

      /* free ARKode memory (to prepare for next call) */
      ARKodeFree(&arkode_mem);
      arkode_mem = NULL;

    } /* end ih loop */

    printf("\nConvergence Test Results, dense output polynomial degree = %i:\n",
           ideg);
    printf("\n  Raw errors per h value:\n");
    printf("  ------------------------------------------\n");
    printf("    h         yerr       dyerr      d2yerr\n");
    printf("  ------------------------------------------\n");
    for (ih = 0; ih < NHVALS; ih++)
    {
      printf("    %.1e   %.2e   %.2e   %.2e\n", (double)hvals[ih],
             (double)yerrs[ih], (double)dyerrs[ih], (double)d2yerrs[ih]);
    }
    printf("  ------------------------------------------\n");

    printf("  Estimated y convergence factors:\n  ");
    for (ih = 1; ih < NHVALS; ih++)
    {
      printf("  %.3f",
             log(yerrs[ih] / yerrs[ih - 1]) / log(hvals[ih] / hvals[ih - 1]));
    }
    yrate2[ideg] = log(yerrs[NHVALS - 1] / yerrs[0]) /
                   log(hvals[NHVALS - 1] / hvals[0]);
    yferr2[ideg] = yerrs[NHVALS - 1];
    printf("  (%.3f, %.0e)\n\n", (double)yrate2[ideg], (double)yferr2[ideg]);

    printf("  Estimated dy convergence factors:\n  ");
    for (ih = 1; ih < NHVALS; ih++)
    {
      printf("  %.3f",
             log(dyerrs[ih] / dyerrs[ih - 1]) / log(hvals[ih] / hvals[ih - 1]));
    }
    dyrate2[ideg] = log(dyerrs[NHVALS - 1] / dyerrs[0]) /
                    log(hvals[NHVALS - 1] / hvals[0]);
    dyferr2[ideg] = dyerrs[NHVALS - 1];
    printf("  (%.3f, %.0e)\n\n", (double)dyrate2[ideg], (double)dyferr2[ideg]);

    printf("  Estimated d2y convergence factors:\n  ");
    for (ih = 1; ih < NHVALS; ih++)
    {
      printf("  %.3f", log(d2yerrs[ih] / d2yerrs[ih - 1]) /
                         log(hvals[ih] / hvals[ih - 1]));
    }
    d2yrate2[ideg] = log(d2yerrs[NHVALS - 1] / d2yerrs[0]) /
                     log(hvals[NHVALS - 1] / hvals[0]);
    d2yferr2[ideg] = d2yerrs[NHVALS - 1];
    printf("  (%.3f, %.0e)\n\n", (double)d2yrate2[ideg], (double)d2yferr2[ideg]);

  } /* end ideg loop */

  /*---- Part III: output overall convergence rate tables ----*/

  printf("\n\nCumulative convergence rates (final errors):\n");
  printf("\n  Hermite Interpolation module:\n");
  printf("  "
         "---------------------------------------------------------------------"
         "------------------------\n");
  printf("   degree |     y             dy           d2y           d3y         "
         "d4y         d5y\n");
  printf("  "
         "---------------------------------------------------------------------"
         "------------------------\n");
  for (ideg = 0; ideg <= ARK_INTERP_MAX_DEGREE; ideg++)
  {
    printf("      %1d   |  %.1f (%.0e)   %.1f (%.0e)   %.1f (%.0e)   %.1f "
           "(%.0e)   %.1f (%.0e)   %.1f (%.0e)\n",
           ideg, (double)yrate[ideg], (double)yferr[ideg], (double)dyrate[ideg],
           (double)dyferr[ideg], (double)d2yrate[ideg], (double)d2yferr[ideg],
           (double)d3yrate[ideg], (double)d3yferr[ideg], (double)d4yrate[ideg],
           (double)d4yferr[ideg], (double)d5yrate[ideg], (double)d5yferr[ideg]);
  }
  printf("  "
         "---------------------------------------------------------------------"
         "------------------------\n");

  printf("\n  Lagrange Interpolation module:\n");
  printf("  ---------------------------------------------------\n");
  printf("   degree |     y             dy           d2y\n");
  printf("  ---------------------------------------------------\n");
  for (ideg = 0; ideg <= ARK_INTERP_MAX_DEGREE; ideg++)
  {
    printf("      %1d   |  %.1f (%.0e)   %.1f (%.0e)   %.1f (%.0e)\n", ideg,
           (double)yrate2[ideg], (double)yferr2[ideg], (double)dyrate2[ideg],
           (double)dyferr2[ideg], (double)d2yrate2[ideg], (double)d2yferr2[ideg]);
  }
  printf("  ---------------------------------------------------\n");

  /* check validity of results */
  flag = verify_results(lambda, rtype, yrate, dyrate, d2yrate, yrate2, dyrate2,
                        d2yrate2);

  /* Clean up and return 'flag' indicating success/failure of tests */
  N_VDestroy(y);
  N_VDestroy(ytest);
  N_VDestroy(dytest);
  N_VDestroy(d2ytest);
  N_VDestroy(d3ytest);
  N_VDestroy(d4ytest);
  N_VDestroy(d5ytest);
  N_VDestroy(yerr);
  N_VDestroy(dyerr);
  N_VDestroy(d2yerr);
  N_VDestroy(d3yerr);
  N_VDestroy(d4yerr);
  N_VDestroy(d5yerr);
  SUNLinSolFree(LS);
  SUNMatDestroy(A);

  SUNContext_Free(&sunctx);
  return (flag);
}

/*-------------------------------
 * Functions called by the solver
 *-------------------------------*/

/* f routine to compute the ODE RHS function f(t,y). */
static int f(sunrealtype t, N_Vector y, N_Vector ydot, void* user_data)
{
  sunrealtype* lambda = (sunrealtype*)user_data;
  NV_Ith_S(ydot, 0) = (*lambda) * (NV_Ith_S(y, 0) - SIN(SUN_RCONST(2.0) * t)) +
                      NV_Ith_S(y, 1) - COS(SUN_RCONST(3.0) * t) +
                      SUN_RCONST(2.0) * COS(SUN_RCONST(2.0) * t);
  NV_Ith_S(ydot, 1) = NV_Ith_S(y, 0) - NV_Ith_S(y, 1) -
                      SIN(SUN_RCONST(2.0) * t) + COS(SUN_RCONST(3.0) * t) -
                      SUN_RCONST(3.0) * SIN(SUN_RCONST(3.0) * t);
  return 0; /* Return with success */
}

/*-------------------------------
 * Private helper functions
 *-------------------------------*/

/* Check function return value...
   opt == 0 means SUNDIALS function allocates memory so check if
   returned NULL pointer
   opt == 1 means SUNDIALS function returns a flag so check if
   flag >= 0
   opt == 2 means function allocates memory so check if returned
   NULL pointer
*/
static int check_flag(void* flagvalue, const char* funcname, int opt)
{
  int* errflag;

  /* Check if SUNDIALS function returned NULL pointer - no memory allocated */
  if (opt == 0 && flagvalue == NULL)
  {
    fprintf(stderr, "\nSUNDIALS_ERROR: %s() failed - returned NULL pointer\n\n",
            funcname);
    return 1;
  }

  /* Check if flag < 0 */
  else if (opt == 1)
  {
    errflag = (int*)flagvalue;
    if (*errflag < 0)
    {
      fprintf(stderr, "\nSUNDIALS_ERROR: %s() failed with flag = %d\n\n",
              funcname, *errflag);
      return 1;
    }
  }

  /* Check if function returned NULL pointer - no memory allocated */
  else if (opt == 2 && flagvalue == NULL)
  {
    fprintf(stderr, "\nMEMORY_ERROR: %s() failed - returned NULL pointer\n\n",
            funcname);
    return 1;
  }

  return 0;
}

/* Verify convergence results...
   We only check convergence rates for y, y', and y'', for both the
   Hermite and Lagrange interpolation modules.  All of the benchmark
   results below were computed/entered manually, by running each
   configuration.  Any convergence rates corresponding to 'final'
   error values >1 are omitted from these checks, as non-convergence
   may occur differently on various architectures.

   We consider sunrealtype precisions {32,64,128} and stiffness values
   lambda = {-1e2, -1e4, -1e6}.
*/
static int verify_results(sunrealtype lambda, int rtype, sunrealtype* yrate,
                          sunrealtype* dyrate, sunrealtype* d2yrate,
                          sunrealtype* yrate2, sunrealtype* dyrate2,
                          sunrealtype* d2yrate2)
{
  int tests   = 0;
  int failure = 0;

  /* single precision checks */
  if (rtype == 32)
  {
    if (SUNRabs(lambda) < 1.1e2)
    { /* lambda = -1e2 */
      /* Hermite module convergence */
      failure += (yrate[0] < 0.8);
      tests++;
      failure += (yrate[1] < 1.8);
      tests++;
      failure += (yrate[2] < 2.2);
      tests++;
      failure += (yrate[3] < 2.0);
      tests++;
      failure += (yrate[4] < 2.7);
      tests++;
      failure += (yrate[5] < 2.7);
      tests++;
      failure += (dyrate[1] < 0.9);
      tests++;
      failure += (dyrate[2] < 1.7);
      tests++;
      failure += (dyrate[3] < 1.8);
      tests++;
      failure += (dyrate[4] < 2.3);
      tests++;
      failure += (dyrate[5] < 2.3);
      tests++;
      failure += (d2yrate[2] < 0.7);
      tests++;
      failure += (d2yrate[3] < 0.9);
      tests++;
      failure += (d2yrate[4] < 1.3);
      tests++;
      failure += (d2yrate[5] < 1.3);
      tests++;
      /* Lagrange module convergence */
      failure += (yrate2[0] < 0.7);
      tests++;
      failure += (yrate2[1] < 1.8);
      tests++;
      failure += (yrate2[2] < 2.1);
      tests++;
      failure += (yrate2[3] < 2.1);
      tests++;
      failure += (yrate2[4] < 2.1);
      tests++;
      failure += (yrate2[5] < 2.1);
      tests++;
      failure += (dyrate2[1] < 0.9);
      tests++;
      failure += (dyrate2[2] < 1.5);
      tests++;
      failure += (dyrate2[3] < 1.9);
      tests++;
      failure += (dyrate2[4] < 1.8);
      tests++;
      failure += (dyrate2[5] < 1.8);
      tests++;
      failure += (d2yrate2[2] < 0.6);
      tests++;
      failure += (d2yrate2[3] < 1.2);
      tests++;
      failure += (d2yrate2[4] < 0.9);
      tests++;
      failure += (d2yrate2[5] < 0.9);
      tests++;
    }
    else if (SUNRabs(lambda) < 1.1e4)
    { /* lambda = -1e4 */
      /* Hermite module convergence */
      failure += (yrate[0] < 0.8);
      tests++;
      failure += (yrate[1] < 1.8);
      tests++;
      failure += (yrate[2] < 2.2);
      tests++;
      failure += (yrate[3] < 2.0);
      tests++;
      failure += (yrate[4] < 3.2);
      tests++;
      failure += (yrate[5] < 3.2);
      tests++;
      failure += (dyrate[1] < 0.9);
      tests++;
      failure += (dyrate[2] < 1.6);
      tests++;
      failure += (dyrate[3] < 1.2);
      tests++;
      failure += (dyrate[4] < 2.2);
      tests++;
      failure += (dyrate[5] < 2.2);
      tests++;
      failure += (d2yrate[2] < 0.7);
      tests++;
      failure += (d2yrate[3] < 0.5);
      tests++;
      /* Lagrange module convergence */
      failure += (yrate2[0] < 0.7);
      tests++;
      failure += (yrate2[1] < 1.8);
      tests++;
      failure += (yrate2[2] < 2.1);
      tests++;
      failure += (yrate2[3] < 2.1);
      tests++;
      failure += (yrate2[4] < 2.1);
      tests++;
      failure += (yrate2[5] < 2.1);
      tests++;
      failure += (dyrate2[1] < 0.9);
      tests++;
      failure += (dyrate2[2] < 1.5);
      tests++;
      failure += (dyrate2[3] < 1.6);
      tests++;
      failure += (dyrate2[4] < 1.5);
      tests++;
      failure += (dyrate2[5] < 1.5);
      tests++;
      failure += (d2yrate2[2] < 0.6);
      tests++;
      failure += (d2yrate2[3] < 0.8);
      tests++;
      failure += (d2yrate2[4] < 0.7);
      tests++;
      failure += (d2yrate2[5] < 0.7);
      tests++;
    }
    else
    { /* lambda = -1e6 */
      /* Hermite module convergence */
      failure += (yrate[0] < 0.8);
      tests++;
      failure += (yrate[1] < 1.7);
      tests++;
      failure += (yrate[2] < 1.3);
      tests++;
      failure += (yrate[3] < 1.1);
      tests++;
      failure += (dyrate[1] < 0.9);
      tests++;
      failure += (dyrate[2] < 0.4);
      tests++;
      failure += (dyrate[3] < 0.1);
      tests++;
      /* Lagrange module convergence */
      failure += (yrate2[0] < 0.7);
      tests++;
      failure += (yrate2[1] < 1.7);
      tests++;
      failure += (yrate2[2] < 1.7);
      tests++;
      failure += (yrate2[3] < 1.7);
      tests++;
      failure += (yrate2[4] < 1.6);
      tests++;
      failure += (yrate2[5] < 1.6);
      tests++;
      failure += (dyrate2[1] < 0.9);
      tests++;
      failure += (dyrate2[2] < 1.1);
      tests++;
      failure += (dyrate2[3] < 0.9);
      tests++;
      failure += (dyrate2[4] < 0.8);
      tests++;
      failure += (dyrate2[5] < 0.8);
      tests++;
    }
  }

  /* double precision checks */
  if (rtype == 64)
  {
    if (SUNRabs(lambda) < 1.1e2)
    { /* lambda = -1e2 */
      /* Hermite module convergence */
      failure += (yrate[0] < 0.8);
      tests++;
      failure += (yrate[1] < 1.8);
      tests++;
      failure += (yrate[2] < 2.6);
      tests++;
      failure += (yrate[3] < 2.4);
      tests++;
      failure += (yrate[4] < 3.1);
      tests++;
      failure += (yrate[5] < 3.1);
      tests++;
      failure += (dyrate[1] < 0.9);
      tests++;
      failure += (dyrate[2] < 1.7);
      tests++;
      failure += (dyrate[3] < 1.8);
      tests++;
      failure += (dyrate[4] < 2.3);
      tests++;
      failure += (dyrate[5] < 2.3);
      tests++;
      failure += (d2yrate[2] < 0.7);
      tests++;
      failure += (d2yrate[3] < 1.0);
      tests++;
      failure += (d2yrate[4] < 1.3);
      tests++;
      failure += (d2yrate[5] < 1.3);
      tests++;
      /* Lagrange module convergence */
      failure += (yrate2[0] < 0.7);
      tests++;
      failure += (yrate2[1] < 1.8);
      tests++;
      failure += (yrate2[2] < 2.4);
      tests++;
      failure += (yrate2[3] < 2.5);
      tests++;
      failure += (yrate2[4] < 2.6);
      tests++;
      failure += (yrate2[5] < 2.6);
      tests++;
      failure += (dyrate2[1] < 0.9);
      tests++;
      failure += (dyrate2[2] < 1.5);
      tests++;
      failure += (dyrate2[3] < 2.4);
      tests++;
      failure += (dyrate2[4] < 2.5);
      tests++;
      failure += (dyrate2[5] < 2.5);
      tests++;
      failure += (d2yrate2[2] < 0.6);
      tests++;
      failure += (d2yrate2[3] < 1.6);
      tests++;
      failure += (d2yrate2[4] < 2.0);
      tests++;
      failure += (d2yrate2[5] < 2.0);
      tests++;
    }
    else if (SUNRabs(lambda) < 1.1e4)
    { /* lambda = -1e4 */
      /* Hermite module convergence */
      failure += (yrate[0] < 0.8);
      tests++;
      failure += (yrate[1] < 1.8);
      tests++;
      failure += (yrate[2] < 2.7);
      tests++;
      failure += (yrate[3] < 2.5);
      tests++;
      failure += (yrate[4] < 3.5);
      tests++;
      failure += (yrate[5] < 3.5);
      tests++;
      failure += (dyrate[1] < 0.9);
      tests++;
      failure += (dyrate[2] < 1.7);
      tests++;
      failure += (dyrate[3] < 1.6);
      tests++;
      failure += (dyrate[4] < 2.6);
      tests++;
      failure += (dyrate[5] < 2.6);
      tests++;
      failure += (d2yrate[2] < 0.7);
      tests++;
      failure += (d2yrate[3] < 0.7);
      tests++;
      /* Lagrange module convergence */
      failure += (yrate2[0] < 0.7);
      tests++;
      failure += (yrate2[1] < 1.8);
      tests++;
      failure += (yrate2[2] < 2.4);
      tests++;
      failure += (yrate2[3] < 2.7);
      tests++;
      failure += (yrate2[4] < 2.7);
      tests++;
      failure += (yrate2[5] < 2.7);
      tests++;
      failure += (dyrate2[1] < 0.9);
      tests++;
      failure += (dyrate2[2] < 1.5);
      tests++;
      failure += (dyrate2[3] < 2.5);
      tests++;
      failure += (dyrate2[4] < 2.6);
      tests++;
      failure += (dyrate2[5] < 2.6);
      tests++;
      failure += (d2yrate2[2] < 0.6);
      tests++;
      failure += (d2yrate2[3] < 1.6);
      tests++;
      failure += (d2yrate2[4] < 2.0);
      tests++;
      failure += (d2yrate2[5] < 2.0);
      tests++;
    }
    else
    { /* lambda = -1e6 */
      /* Hermite module convergence */
      failure += (yrate[0] < 0.8);
      tests++;
      failure += (yrate[1] < 1.8);
      tests++;
      failure += (yrate[2] < 2.7);
      tests++;
      failure += (yrate[3] < 2.4);
      tests++;
      failure += (yrate[4] < 3.6);
      tests++;
      failure += (yrate[5] < 3.6);
      tests++;
      failure += (dyrate[1] < 0.9);
      tests++;
      failure += (dyrate[2] < 1.6);
      tests++;
      failure += (dyrate[3] < 1.4);
      tests++;
      failure += (dyrate[4] < 2.6);
      tests++;
      failure += (dyrate[5] < 2.6);
      tests++;
      failure += (d2yrate[2] < 0.7);
      tests++;
      failure += (d2yrate[3] < 0.6);
      tests++;
      /* Lagrange module convergence */
      failure += (yrate2[0] < 0.7);
      tests++;
      failure += (yrate2[1] < 1.8);
      tests++;
      failure += (yrate2[2] < 2.4);
      tests++;
      failure += (yrate2[3] < 2.6);
      tests++;
      failure += (yrate2[4] < 2.7);
      tests++;
      failure += (yrate2[5] < 2.7);
      tests++;
      failure += (dyrate2[1] < 0.9);
      tests++;
      failure += (dyrate2[2] < 1.5);
      tests++;
      failure += (dyrate2[3] < 2.5);
      tests++;
      failure += (dyrate2[4] < 2.6);
      tests++;
      failure += (dyrate2[5] < 2.6);
      tests++;
      failure += (d2yrate2[2] < 0.6);
      tests++;
      failure += (d2yrate2[3] < 1.6);
      tests++;
      failure += (d2yrate2[4] < 2.0);
      tests++;
      failure += (d2yrate2[5] < 2.0);
      tests++;
    }
  }

  /* extended precision checks */
  if (rtype == 128)
  {
    if (SUNRabs(lambda) < 1.1e2)
    { /* lambda = -1e2 */
      /* Hermite module convergence */
      failure += (yrate[0] < 0.8);
      tests++;
      failure += (yrate[1] < 1.8);
      tests++;
      failure += (yrate[2] < 2.7);
      tests++;
      failure += (yrate[3] < 2.7);
      tests++;
      failure += (yrate[4] < 3.3);
      tests++;
      failure += (yrate[5] < 3.3);
      tests++;
      failure += (dyrate[1] < 0.9);
      tests++;
      failure += (dyrate[2] < 1.7);
      tests++;
      failure += (dyrate[3] < 2.1);
      tests++;
      failure += (dyrate[4] < 2.6);
      tests++;
      failure += (dyrate[5] < 2.6);
      tests++;
      failure += (d2yrate[2] < 0.7);
      tests++;
      failure += (d2yrate[3] < 1.3);
      tests++;
      failure += (d2yrate[4] < 1.6);
      tests++;
      failure += (d2yrate[5] < 1.6);
      tests++;
      /* Lagrange module convergence */
      failure += (yrate2[0] < 0.7);
      tests++;
      failure += (yrate2[1] < 1.8);
      tests++;
      failure += (yrate2[2] < 2.5);
      tests++;
      failure += (yrate2[3] < 2.8);
      tests++;
      failure += (yrate2[4] < 2.8);
      tests++;
      failure += (yrate2[5] < 2.8);
      tests++;
      failure += (dyrate2[1] < 0.9);
      tests++;
      failure += (dyrate2[2] < 1.5);
      tests++;
      failure += (dyrate2[3] < 2.5);
      tests++;
      failure += (dyrate2[4] < 2.8);
      tests++;
      failure += (dyrate2[5] < 2.8);
      tests++;
      failure += (d2yrate2[2] < 0.6);
      tests++;
      failure += (d2yrate2[3] < 1.6);
      tests++;
      failure += (d2yrate2[4] < 2.0);
      tests++;
      failure += (d2yrate2[5] < 2.0);
      tests++;
    }
    else if (SUNRabs(lambda) < 1.1e4)
    { /* lambda = -1e4 */
      /* Hermite module convergence */
      failure += (yrate[0] < 0.8);
      tests++;
      failure += (yrate[1] < 1.8);
      tests++;
      failure += (yrate[2] < 2.7);
      tests++;
      failure += (yrate[3] < 2.5);
      tests++;
      failure += (yrate[4] < 3.5);
      tests++;
      failure += (yrate[5] < 3.5);
      tests++;
      failure += (dyrate[1] < 0.9);
      tests++;
      failure += (dyrate[2] < 1.7);
      tests++;
      failure += (dyrate[3] < 1.6);
      tests++;
      failure += (dyrate[4] < 2.6);
      tests++;
      failure += (dyrate[5] < 2.6);
      tests++;
      failure += (d2yrate[2] < 0.7);
      tests++;
      failure += (d2yrate[3] < 0.7);
      tests++;
      /* Lagrange module convergence */
      failure += (yrate2[0] < 0.7);
      tests++;
      failure += (yrate2[1] < 1.8);
      tests++;
      failure += (yrate2[2] < 2.4);
      tests++;
      failure += (yrate2[3] < 2.7);
      tests++;
      failure += (yrate2[4] < 2.7);
      tests++;
      failure += (yrate2[5] < 2.7);
      tests++;
      failure += (dyrate2[1] < 0.9);
      tests++;
      failure += (dyrate2[2] < 1.5);
      tests++;
      failure += (dyrate2[3] < 2.5);
      tests++;
      failure += (dyrate2[4] < 2.6);
      tests++;
      failure += (dyrate2[5] < 2.6);
      tests++;
      failure += (d2yrate2[2] < 0.6);
      tests++;
      failure += (d2yrate2[3] < 1.6);
      tests++;
      failure += (d2yrate2[4] < 2.0);
      tests++;
      failure += (d2yrate2[5] < 2.0);
      tests++;
    }
    else
    { /* lambda = -1e6 */
      /* Hermite module convergence */
      failure += (yrate[0] < 0.8);
      tests++;
      failure += (yrate[1] < 1.8);
      tests++;
      failure += (yrate[2] < 2.5);
      tests++;
      failure += (yrate[3] < 2.2);
      tests++;
      failure += (yrate[4] < 3.4);
      tests++;
      failure += (yrate[5] < 3.4);
      tests++;
      failure += (dyrate[1] < 0.9);
      tests++;
      failure += (dyrate[2] < 1.5);
      tests++;
      failure += (dyrate[3] < 1.2);
      tests++;
      failure += (dyrate[4] < 2.4);
      tests++;
      failure += (dyrate[5] < 2.4);
      tests++;
      failure += (d2yrate[2] < 0.6);
      tests++;
      failure += (d2yrate[3] < 0.4);
      tests++;
      /* Lagrange module convergence */
      failure += (yrate2[0] < 0.7);
      tests++;
      failure += (yrate2[1] < 1.8);
      tests++;
      failure += (yrate2[2] < 2.4);
      tests++;
      failure += (yrate2[3] < 2.4);
      tests++;
      failure += (yrate2[4] < 2.5);
      tests++;
      failure += (yrate2[5] < 2.5);
      tests++;
      failure += (dyrate2[1] < 0.9);
      tests++;
      failure += (dyrate2[2] < 1.5);
      tests++;
      failure += (dyrate2[3] < 2.3);
      tests++;
      failure += (dyrate2[4] < 2.4);
      tests++;
      failure += (dyrate2[5] < 2.4);
      tests++;
      failure += (d2yrate2[2] < 0.6);
      tests++;
      failure += (d2yrate2[3] < 1.6);
      tests++;
      failure += (d2yrate2[4] < 2.0);
      tests++;
      failure += (d2yrate2[5] < 2.0);
      tests++;
    }
  }

  /* output result */
  printf("\nTotal failures: %i (out of %i)\n", failure, tests);
  return (0);
}

/*---- end of file ----*/
